Field of the Invention
This invention generally relates to a multiple bicycle sprocket assembly. More specifically, the present invention relates to a multiple bicycle sprocket assembly having a rotational central axis and configured to be mounted on a bicycle hub assembly.
Background Information
A plurality of rear sprockets are attached to a bicycle rear hub assembly (see EP1342657A2). The respective rear sprockets have different numbers of teeth. A combination of the numbers of teeth of the respective rear sprockets, that is, a tooth combination of the rear sprockets is set according to a characteristic of a course, for example.
In the case in which a rider attaches importance to riding at a high speed in a course having many flat roads or the like, generally, a sprocket having a small number of teeth is used for the rear sprocket on a top side. On the other hand, in the case in which the rider attaches importance to comfortable riding in a course having many uphills or the like, a sprocket having a large number of teeth is used for the rear sprocket on a low side.
In the conventional rear sprocket, it is possible to constitute a gear ratio which attaches importance to a speed, but it is difficult to constitute the gear ratio at which pedal stepping is very light. On the other hand, in the conventional rear sprocket, it is possible to constitute the gear ratio at which the pedal stepping is very light, but it is difficult to constitute the gear ratio which attaches importance to the speed. In other words, the conventional rear sprocket does not have such a configuration as to simultaneously satisfy both of the gear ratio which attaches importance to the speed and the gear ratio at which the pedal stepping is light.
In consideration of the problem, it is an object of the present invention to provide a multiple bicycle sprocket assembly capable of constituting a gear ratio in a wide range.